The Federal Communications Commission took the general aviation world by surprise when it said in a recent report it will prohibit the sale or use of 121.5 MHz emergency locator transmitters, effective in August.

The FCC said its rules have been amended to "prohibit further certification, manufacture, importation, sale or use of 121.5 MHz ELTs." The FCC says that if the 121.5 units are no longer available, aircraft owners and operators will "migrate" to the newer 406.0-406.1 MHz ELTs.